UAT-9921 is a China-nexus threat actor active since 2019, tracked by Cisco Talos. In 2026, they were observed deploying 'VoidLink', a sophisticated modular framework primarily targeting Linux systems (IoT, Critical Infrastructure). Unique characteristics include the use of AI-enabled IDEs for rapid development (ZigLang implant, GoLang backend), P2P mesh networking for C2, and advanced persistence via eBPF rootkits. They target Technology and Financial sectors exploiting Java serialization vulnerabilities (Apache Dubbo).
The same group is tracked under different names by different vendors.
| Vendor | Name |
|---|---|
| OSINT | VoidLink Operator |
No techniques mapped yet.
No IOCs extracted yet from reports naming this actor.
Every report in the Global Intel Library that names UAT-9921, newest first. Open any report to see the full analysis with provenance.
No reports in the Lore library name this actor yet.
Indicators from free threat feeds (abuse.ch ThreatFox, AlienVault OTX) attributed to UAT-9921. Each row shows why it was linked and where it came from.
No feed indicators linked to this actor yet. Feeds are checked every hour.
Open-source reports about this actor collected from MISP Galaxy.